Pittsburg Water Treatment Plant - Executive Summary |
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EXECUTIVE SUMMARY The Accidental Release Prevention and Emergency Response Policies at Pittsburg Water Treatment Plant The Pittsburg Water Treatment Plant (the "Plant") is owned by the City of Pittsburg (the "City") and is located at 300 Olympia Drive. It operates as a division of its Public Services Department. The City is committed to providing needed services to local residents, businesses and visitors to Pittsburg, and to being a positive influence on the community. This includes respect for the safety of city workers and the public, as well as concern for the environment. The City of Pittsburg values its employees' efforts to find safer, more effective and more efficient ways of providing service to the community. Regular safety meetings are held, and employees are encouraged to look for ways to reduce the risk to the community and environment through implementation of new technology and procedures. This commitment to safe and environmentally sound operations is documented in t he policy and compliance manuals, and the mission statement, which are available to all employees. A copy of the Plant's Accidental Release Prevention Program policy is included as Figure 1-1. The plant also trains and requires all employees to be familiar with the Operations Plan and Plant Operations Manual kept on site. This Manual includes all operational procedures, from normal operation to emergency and non-emergency plant shut-downs. A HAZOP Study was completed in January 1995, regarding the use and handling of chlorine and ammonia at the Plant. This study complies with OSHA rule 1910.119, "Process Safety Management of Highly Hazardous Chemicals." A copy is kept at reference library at the Plant. A Risk Management and Prevention Program developed by EQE International was also adopted for the facility in 1995. Stationary source safety and environmental programs include the following: weekly tailgate talks with all plant staff present; semi-annual Safety Meetings, periodic Self - Contained Breathing Apparatus (SCBA) training, including refresher courses for all staff at the point a new employee is hired; instruction on handling of chemicals and the use or Personal Protective Equipment (PPE). In addition to the above, all new employees receive orientation and a copy of the City's Hazard Communications Policy, including instruction on how to read and understand MSDS sheets posted at the Water Plant, and the City's Injury & Illness Prevention Plan. In addition, there are regularly scheduled, and unscheduled, safety inspections of all city facilities by the Public Services Department Safety Committee, which operates in conjunction with the City of Pittsburg Safety Committee. The latter group involves itself in generalized safety concerns across all city departments, while the Public Services committee specializes in maintenance and operations functions of the department. Safety inspections by Public Services Department personnel occur most often at the Water Treatment Plant, as this has been determined to be a safety-sensitive area. Recommendations resulting from these inspections are given to the Safety Committee and to the Plant Superintendent for review and appropriate action. A Description of the Pittsburg Water Treatment Plant and the regulated substances handled Description of Stationary Source As stated previously, the Pittsburg Water Treatment Plant is located at 300 Olympia Drive in Pittsburg, approximately three miles south of Suisun Bay and one mile south of State Highway 4. The facility occupies an area of approximately 15 acres. The plant operates as a division of the Public Services Department of the City of Pittsburg. As a municipal facility, the plant is staffed 24 hours each day by public employees who meet or exceed training and certification requirements for Water Treatment Plant operators or technicians. Construction contractors and consultants are hired on occasion to complete those projects deemed to be outside t he normal operations and maintenance of the plant. Homes border the plant property to the north, east and south. To the west is a strip of undeveloped land, beyond which lies Delta View Golf Course and Stoneman Park. The nearest residences are approximately 350 feet away from chlorine and ammonia handling areas. They are a constant reminder of the need to give top priority to operating in a safe and environmentally sound manner. Information on the location of sensitive receptors in relation to the facility can be found in the Off-Site Consequence Analysis included in this document. The Pittsburg Water Treatment Plant began operation in 1953, with a rated capacity of 8 million gallons per day, for the treatment and disinfection of raw water. The facility underwent modernization and upgrades in 1976-77, which increased the rated capacity to 16 million gallons per day. In 1988-90, the facility was modernized and upgraded once more, and the capacity of the plant reached its current l evel of 32 million gallons per day. In 1998-99, the plant replaced its on- site 6 million gallon reservoir. The systems for handling chlorine and ammonia were installed during the 1988-90 modernization. Description of the Substances Handled Chlorine is used at the Water Treatment Plant to disinfect raw water drawn from the Contra Costa Canal or from wells operated by the City. Elemental chlorine is a greenish-yellow gas that can be readily compressed into a clear, amber-colored liquid. Chlorine is typically packaged as a liquefied gas under pressure in steel containers. The liquid is about 1? times as heavy as water, and the gas is about 2? times as heavy as air. The liquid vaporizes readily at normal atmospheric temperature and pressure. Chlorine has an unmistakable irritating and pungent odor. Liquid chlorine is a skin irritant and can cause severe damage, resembling a burn, to body tissues. Chlorine gas in low concentrations is an irritant to mucous membranes and the respiratory system. Exposure to large concentrations of chlorine gas can cause significant impairment of the respiratory system. Anhydrous Ammonia is used at the Plant in combination with chlorine, to control the amount of trihalomethanes (THMs) in potable water. Ammonia is a colorless gas with a very irritating odor, and is highly soluble in water. When ammonia is released to the atmosphere, it creates a dense, white fog because it reacts with water in the atmosphere. At normal temperatures and pressures, anhydrous ammonia is a gas. Pressurizing the gas in a container liquefies it. Ammonia is commonly transported and stored as a liquid. At atmospheric pressure, the liquid density of ammonia is approximately 2/3 that of water. Ammonia gas is lighter than air, so releases of vapor to the atmosphere will rise. Ammonia in the ambient air has an intense effect upon the mucous membranes of the eyes, nose, throat and lungs. Exposure to a high concentration of ammonia can produce corrosive action on these tissues, which can lead to impairment of the respiratory system. Description of Plant Process - Chlorine The chlorine system is made up of chlorine supply cylinders, piping and valves. The chlorine cylinders are owned and maintained by the chlorine supplier (currently All Pure Chemical Company.) Chlorine is supplied in 1-ton cylinders and stored in the chlorine storage room. The chlorine cylinders are owned and maintained by the chlorine supplier. (Note: While the current chlorine supplier is All Pure Chemical Company, the contract for chlorine supply is evaluated and awarded on an annual basis.) Chlorine is stored in liquid form, under pressure at ambient temperature. A maximum of ten chlorine cylinders (20,000 pounds) are on-site in the chlorine storage room at any one time. Receipt of chlorine supply occurs only on Monday through Friday, during normal business hours. Additional facility personnel are on-site at this time to respond if a release were to occur during the d elivery operation. Chlorine cylinders are unloaded by the vendor outside the chlorine storage room. Empty cylinders are loaded at the same location. Truck operators are trained by the vendor and are responsible for visual inspection of chlorine cylinders each time they are on the Plant site. Two Plant operators work together when moving chlorine cylinders, such as removing empty cylinders and hooking up full cylinders. The chlorinators, located in the chemical feed room control the flow rate of chlorine to the water injection locations. Water injection acts as a motive force to draw the chlorine from the chlorinators to the injection points. A vacuum regulator valve is located upstream of the chlorinators. The pressure of the chlorine transfer lines and equipment, from the vacuum regular, through the chlorinator, to the water injection points, is below atmospheric pressure. During operation, two chlorine cylinders are connected to the process, feeding chlorine to the chlorinators , and two backup cylinders are connected to the process by blocked in by closed supply valves. Each on-line or backup cylinder is connected to the chlorine-piping manifold through a flexible stainless steel tubing connection, or "pigtail." All chlorine cylinders are strapped to their support cradles with steel chains, regardless of whether or not they are connected to the process. The pressure in the chlorine cylinders varies with the ambient temperature inside the chlorine storage room. The pressure in the cylinders typically ranges from 72 psig (60 F) to 143 psig (100 F). Field instruments in the chlorine storage room include pressure gauges installed downstream of the chlorine supply cylinders and upstream of the vacuum regulator, one for each pair of chlorine cylinders connected to the process. Weight scales are installed at each pair or chlorine cylinders connected to the process. A vacuum pressure gauge and a high-pressure switch that alarms to the control console are locate d downstream of the chlorine vacuum regulator. Low pressure switches (PSL-601-1/2) are installed downstream of the chlorine supply cylinders and upstream of the vacuum regulator, one for each pair of chlorine cylinders connected to the process. The high-and low-pressure switches alarm to the control console. Chlorine Scrubber System The chlorine storage room is fitted with a scrubber system, designed to remove chlorine from the atmosphere in the chlorine storage room if an accidental release were to occur. The following describes the operation and design of the scrubber system: The scrubber system operates by circulating approximately 250 gallons per minute of 15 % sodium hydroxide (NaOH) solution through a venturi to a NaOH storage/separator vessel with a 2,000 gallon operating capacity. The circulation through the venturi draws the atmosphere out of the chlorine storage room, through ducts that are located along the floor of the storage room, and contacts the vapor (air and chlori ne) from the storage room with the NaOH solution, neutralizing the chlorine. Two chlorine leak detectors are installed in the chlorine storage room. Upon detection of 1 ppm of chlorine in the storage room, a warning alarm will sound at the operator console in the Operations Building. Upon detection of 3 ppm of chlorine in the storage room, a second warning alarm will be sounded at the operator console, and the storage room scrubber system will be started. That is, the NaOH circulation pump will be started. The scrubber system cannot be shut off except by direct operator intervention. The chlorine storage room is provided with its own HVAC system, including inlet louvers and an exhaust fan. The louvers are normally closed and the fan is off, except during hot ambient conditions, such a hot summer day. When the scrubber system is activated, the chlorine storage room HVAC inlet louvers are interlocked to close and the exhaust fan is shut off. The design of the chlorine storage room scrubber system is described in the Water Treatment Plant Expansion Operation and Maintenance Manual, Volumes III, IV & V, Chemical Equipment, Electrical, Instrumentation and Controls, September 1988, Engineer: Camp, Dresser & McKee, Contractor: Lawson Mechanical Contractors, and is located in the Plant reference library. The following information, included in the subject manual, was extracted from Design Performance Calculations for Pittsburg WTP, Emergency Chlorine Exhaust Project, EST Job File #EC89.820, dated September 28, 1989, and was provided by EST Corporation, designer of the scrubber system: "The 14" Emergency Chlorine Scrubber/Separator Package is designed to handle a slow leak of 2,000 lb. over a two-hour period into a 9500 cu. ft. room. The system will lower the concentration to 1 ppm in less than 3? hours total. A duct resistance of 2" WC has been allowed at a scrubber capacity of 1700 cfm (The 14" TYPE 910 Scrubber will provide a 3 ?" WC draft a nd the separator will have a maximum pressure drop of 1?" WC.) The separator will initially be filled with 2000 gal of 15% NaOH solution. The liquid temperature rise will not exceed 74 F." Description of Plant Process Ammonia The ammonia system process flow diagram may be found in the Water Treatment Plant Expansion Drawings, Contract No. 87-02, Volumes 1 and 2, September 1988, Camp Dresser & McKee, Inc. located in the Plant reference library. The diagram is titled, Chemical Feed Schematics V, Sheet M-8, (82 of 147). The ammonia system is made up of the ammonia supply vessel, piping and valves. Ammonia is stored in liquid form, under pressure at ambient temperature, in the ammonia supply vessel, T-C-901. The vessel is owned by the City and is maintained by the ammonia supplier, currently LaRoche Industries. LaRoche installed the vessel in 1990, and is responsible for inspections of the vessel as needed. The last inspection of this vessel was in 1998. (Note: The contract for ammonia supply is evaluated and awarded on an annual basis.) Ammonia is unloaded by the vendor into the vessel. Plant operators stand by during the ammonia supply vessel filling operation. Receipt of ammonia supply occurs only on Monday through Friday, during normal business hours. Additional facility personnel are on-site at this time to respond if a release were to occur during the delivery operation. Truck operators are trained by the vendor and are responsible for visual inspection of regulator valves and other safety equipment related to the vessel each time they are on the Plant site. The flow rate of ammonia to the water injection locations is controlled by ammoniators located in the chemical feed room. Water injection acts as a motive force to draw the ammonia from the ammoniators to the injection points. A vacuum regulator valve is located upstream of the ammoniators. The pressure of the ammonia transfer lines and equipment, from the vacuum regulator, thr ough the ammoniator, to the water injection points, is below atmospheric pressure. The pressure in the ammonia supply vessel varies with the ambient temperature. The pressure in the vessel typically ranges from 95 psig (60 F) to 195 psig (100 F). The storage vessel capacity is 1,000 gallons. The maximum amount of ammonia stored in the supply vessel to 850 gallons (4,375 pounds at 60 F). The vessel is equipped with a continuous level transmitter with indication to the control console. This indicator signal (LE-611) is configured with high-level (at 900 gallons) and low-level (at 100 gallons) alarms. The ammonia supply vessel is designed with a maximum operating pressure of 265 psig and is protected by two relief valves that vent to the atmosphere. Additional field instrumentation at the ammonia supply vessel includes a pressure gauge and a local level indicator. Downstream of the ammonia vacuum regulator are a vacuum pressure gauge and a high-pressure switch that alarms to the contr ol console. Two pressure relief valves are installed on the ammonia supply vessel. Worst Case Release Scenario and Alternative Release Scenario(s) The Pittsburg Water Treatment Plant commissioned an Off-Site Consequence Analysis from respected environmental consultants EQE International of San Francisco. The objectives of the study were: " To provide information necessary for realistic emergency response and planning " To demonstrate risk management improvements resulting from the Risk Management and Prevention Program of 1995, including the impact those improvements would have on off- site consequences, and, " To provide the public with information regarding the potential risk of hazardous materials in their neighborhoods, the risk management practices of facilities using these materials, and the protective action that may need to be taken by the public if a major release of these materials ever occurred. The analysis included in this report is based upon mod eling of several representative release scenarios for chlorine and ammonia. It includes a description of the two substances, as well as their use and storage; a description of the computer models used in the analysis and the consequences of an accidental release on the area surrounding the Pittsburg Water Treatment Plant. Five release scenarios were selected for modeling. They were: Scenario One assumes a leak in a section of the 1-inch chlorine piping upstream of the vacuum regulator, which could be due to a seismic event or mechanical impact. The worst case for a line failure is a complete break. Two 1-ton cylinders are in service at one time, with a maximum capacity of 4,000 pounds that could be released. It is assumed 30 minutes would elapse before the leak is isolated. Scenario Two assumes the lead core in a fusible plug fails completely, resulting in a .03 inch hole in a single 1-ton chlorine cylinder. The leak occurs below the liquid level, and is assumed to occur 30 minutes before the leak is isolated. Scenario Three assumes that a ? inch diameter hole occurs in the flexible tubing between the chlorine cylinders and the piping manifold. It is assumed to occur 30 minutes before the leak is isolated. Scenario Four assumes that a inch pressure relief device opens prematurely on the ammonia supply vessel and sticks open, releasing gaseous ammonia to the atmosphere. It is assumed 30 minutes elapse before the leak can be isolated. Scenario Five assumes a break occurs in the 1-inch diameter loading hose during delivery of ammonia to the plant from a vendor's truck. It is assumed the excess flow valve on the ammonia supply truck fails, and that 10 minutes elapse before the leak is isolated. Each scenario considers seasonal variations in wind speed and direction, ambient temperature and relative humidity. Topography in the area surrounding the Plant is also considered. The model assigns for each scenario two levels or zones of concern. The Protective Acti on Zone is the area within which people would be notified to "Shelter-In-Place" or, in the case of an extended release, evacuate. The Notification Zone is that area where no evacuation would be necessary but within which people would be notified of an accidental release. There are 14 Sensitive Receptors within one mile of the Plant, and 30 additional Sensitive Receptors within three miles of the Plant. These include schools, convalescent hospitals, board and care homes and child care facilities. General Accidental Release Prevention Program and Chemical-Specific Prevention Steps Management System The Pittsburg Water Treatment Plant has developed a management system to plan, organize, implement and control the risk management program elements. This system satisfies the requirements of Section 2735.6 of the CalARP regulation, and ensures that risk management program elements are developed and continually improved. All records associated with the prevention program elements are retai ned for a minimum of five years, unless otherwise specified in the CalARP regulation. " Planning The Plant has an overall risk management policy that clearly identifies the goals and objectives of the risk management program. " Organizing The Plant Superintendent was designated as the person responsible for the risk management program elements. While this authority may be further delegated to subordinate staff, contract workers or consultants, the size of the facility does not permit such assignments at this time. " Implementing The Plant Superintendent is responsible for ensuring all appropriate persons are trained in risk management procedures, implementation of the procedures, and documentation. Refresher training is provided on an as-needed basis, but is conducted at a minimum following any changes to procedures, or following reauthorization. " Controlling The Plant Superintendent and his designees will conduct periodic internal reviews or audit s against the goals and objectives of the program element. Annually, these procedures are reviewed, revised and reauthorized to ensure they remain accurate and reflect current practices. Chemical-Specific Prevention Steps Chlorine System A. The chlorine supply cylinders are stored in an enclosed storage room. During normal operation, the doors into the room are closed. The chlorine storage room is provided with a scrubber system, which is described in detail in the first section of this document. B. The chlorine cylinder is designed with cylinder heads (ends) that are concave, or curved into the cylinder. This allows mounting of the cylinder valves inside the end. This design reduces the likelihood of damage to the cylinder valves that may be caused by a collision with tools or equipment. C. The chlorine handling system utilizes a vacuum regulator, which minimizes the amount of chlorine that is handled above atmospheric pressure. All chlorine piping and equ ipment that operate above atmospheric pressure are located inside the chlorine storage room. D. The chlorine storage room, which is part of the Operations Building, is designed in accordance with the Uniform Building Code (UBC) 1988 edition. E. The chlorine system is installed in accordance with the recommendations of the Chlorine Institute. F. Two chlorine leak detectors are installed in the chlorine storage room. Upon detection of 1 ppm of chlorine in the storage room, a warning alarm will be sounded at the operator console in the Operations Building. Upon detection of 3 ppm of chlorine in the storage room, a second warning alarm will be sounded at the operator console, and the storage room scrubber system will be started. The storage room scrubber system is designed to remove 2,000 pounds of chlorine from the chlorine storage room over a 3 ? hour period. Shutting off the scrubber system requires operator intervention. G. The chlorine storage room is provided with its own HVAC system, including inlet louvers and an exhaust fan. The louvers are normally closed and the fan is off, except during hot ambient conditions, such a hot summer day. When the scrubber system is activated, the chlorine storage room HVAC inlet louvers are interlocked to close and the exhaust fan is shut off. H. The chlorine vacuum regulator closes when the downstream pressure exceeds the regulator setting (which may be due to a leak or break in the line or equipment downstream of the regulator. I. Chlorine supply cylinders, both full and empty, are strapped down with steel chains to prevent movement. Each cylinder is individually strapped down. J. Flexible connectors, or pigtails, are installed between the chlorine supply cylinders and the chlorine piping manifold. Use of pigtails reduces the likelihood of accidental chlorine release caused by inadvertent movement, which may result from a seismic event or mechanical impact, of th e chlorine cylinders. Pigtails are changed every six months, in January and July of each year, or when excessive wear is noted. K. Pressure gauges (field indicators) are installed downstream of the chlorine supply cylinders and upstream of the vacuum regulator, one for each pair on-line chlorine cylinders. A vacuum pressure gauge is installed downstream of the vacuum regulator. Weight scales (field indictors) are installed at each pair of on-line chlorine cylinders. L. Low-pressure switches (PSL-601-1/2) are installed downstream of the chlorine supply cylinders and upstream of the vacuum regulator, one for each pair of on-line chlorine cylinders. A high vacuum pressure switch is installed downstream of the vacuum regulator. M. Personal Protective Equipment (PPE) is available to isolate a chlorine leak. All Pittsburg Water Plant personnel are trained in the use of MSA 401 breathing apparatus and chemical suits. Four each of MSA 401s and chemical suits are loca ted on-site; two each are located outside the chlorine storage room on the north wall, and two each are located outside the chemical feed room on the south wall. N. A Chlorine Institute Emergency Kit "B" for ton containers, used for sealing leaks in chlorine cylinders, is available on-site, located in the chemical room, which is adjacent to the chemical storage room. The B Kit is inspected on a quarterly basis to ensure it is complete and all parts are in good condition. All Pittsburg Water Plant personnel are trained in how to use the B Kit. O. There is a sprinkler system in the chlorine storage room, which was installed in accordance with the local fire code. No flammable or combustible materials are stored in the chlorine storage room. P. The Plant is crewed 24 hours per day. The operating staff continuously monitors the entire operation. Operators perform surveillance, or rounds, of the entire facility, including the ammonia and chlorine systems, at least every four hours. Usage of all chemicals, including chlorine, is recorded every 24 hours. Ammonia System A. The ammonia handling system utilizes a vacuum regulator, which minimizes the amount of ammonia that is handled above atmospheric pressure. The vacuum regulator is located as close to the ammonia supply vessel as practical, approximately 5 feet. B. The current ammonia supplier, LaRoche Industries, installed the ammonia system. The ammonia supply vessel, C-T-901, was fabricated in accordance with the ASME Boiler and Pressure Vessel Code, Section VIII. C. The ammonia system vacuum regulator closes when the downstream pressure exceeds the regulator setting, which may be due to a leak or break in the line or equipment downstream of the regulator. D. A pressure gauge (field indicator) is installed at the ammonia supply vessel. A vacuum pressure gauge is installed downstream of the vacuum regulator. A local level indicator (field indicator) is in stalled at the ammonia supply vessel. E. A level transmitter with indication (LE-611) to the control console is installed at the ammonia supply vessel. The level indicator has a low setting (100 gallons) and a high setting (900 gallons) that alarm to the control console. A high vacuum pressure switch is installed downstream of the vacuum regulator. F. Two pressure relief valves are installed on the ammonia supply vessel. G. PPE is available to isolate an ammonia leak. All Pittsburg Water Plant personnel are trained in the use of MSA 401 breath apparatus and chemical suits. Four each of MSA 401s and chemical suits are located on-site; two each are located outside the chlorine storage room on the north wall, and two each are located outside the chemical feed room on the south wall. H. A fire water hydrant is located within 50 feet of the ammonia supply vessel. This hydrant provides the capability to "knock down" an ammonia leak with firewater, which may min imize possible off-site impact of an ammonia release. I. The Plant is crewed 24 hours per day. The operating staff continuously monitors the entire operation. Operators perform surveillance, or rounds, of the entire facility, including the ammonia system, at least one every four hours. Usage of all chemicals, including ammonia, is recorded every 24 hours. Prevention Program Elements Process Safety Information The following process safety information is available at the Pittsburg Water Treatment Plant: " Operating Standards and Procedures are available for the entire operation of the Pittsburg Water Plant, and are located in the control area of the Operations Building. A written procedure is available for changing the chlorine supply cylinders; that is, moving empty cylinders and replacing them with full cylinders at the on-line location in the chlorine storage room. " Water Treatment Plant Expansion, Contract Documents and Specifications, Contract No. 87- 02, Volumes 1 & 2, September 1988, Camp, Dresser & McKee Inc., located in the Plant reference library " Water Treatment Plant Expansion, Drawings, Contract No. 87-02, Volumes 1 & 2, September 1988, Camp, Dresser & McKee Inc., located in the Plant reference library " Water Treatment Plant Expansion, Operation and Maintenance Manual, Volumes III, IV, & V, Chemical Equipment, Electrical, Instrumentation and Controls, September 1988, Engineer: Camp, Dresser & McKee, Contractor: Lawson Mechanical Contractors, located in the Plant reference library In addition, the following logs are maintained by Plant personnel to provide a record of the facility operation: " Plant operations log, located in the control area " Maintenance log, located in the maintenance shop Process Hazard Analysis A Hazard and Operability Study was conducted on January 9, 1995 regarding the use and handling of chlorine and ammonia at the Pittsburg Water Treatment Plant. A Hazard and Operability ( HAZOP) Study was conducted on January 9, 1995, regarding the use and handling of chlorine and ammonia at the Pittsburg Water Plant. This study complies with OSHA rule 1910.119, "Process Safety Management of Highly Hazardous Chemicals." A copy of the HAZOP Study report is available at the Pittsburg Water Plant. HAZOP Study Deviations The study was conducted primarily using the HAZOP Study deviation guideword technique. The guidewords, in conjunction with key process parameters, prompt the HAZOP Study team to brainstorm possible causes and potential consequences of deviations from design operation. For example, the deviation "NO FLOW" would prompt the leader to ask the team, "What could cause no flow in this section or line segment?" The "Possible Cause" and "Potential Consequence" scenarios are documented in the study worksheets. The "Existing Systems and Procedures: (safeguards) that reduce the risk associated with the specific cause / consequence scenario are then discussed an d documented. For scenarios involving significant risk, "Recommendations" that the team believes may further reduce risk or improve the operability of the facility are also documented. The specific steps of the HAZOP Study methodology used in this study were: u Choose a study section or mode u Apply a deviation (guideword + parameter) u Brainstorm causes of the deviation u Develop each cause to its global consequence(s) u Identify existing safeguards u Qualitatively assess the risk of the scenario u If warranted, make recommendations to reduce risk and / or improve the operability of the facility The systematic approach of a HAZOP Study requires that deviations (guidewords + parameters) be uniformly applied to all sections under study. The following deviations were used for each study session: No Flow Leak / Rupture Wrong Reaction1 More Flow Human Factors No Mixing1 Less FlowMechanical Seal Damage More Mixing 1 Reverse Flow Exchanger Tube Leak1 Less Mixing1 Misdirected Flow Sampling1 Service Failure1 More Temperature Maintenance1 Instrumentation1 Less Temperature Wrong Material1 Testing1 More Pressure Corrosion / Erosion1 Relief1 Less Pressure Pipe Specification Break1 Ignition1 More Level No Reaction1 Isolation1 Less Level More Reaction1 Abnormal Operation1 Wrong Concentration Less Reaction1 External Events1 Contamination As-well-as Reaction1 Safety1 Startup / Shutdown Wrap-up Discussions The HAZOP Study techniques was used to analyze line-by-line the AHM handling systems at the Pittsburg Water Plant. However, the HAZOP Study technique may not document all the general issues affecting the health and safety of the work place employee or identify all potential AHM releases that could have off-site impact. In addition to the line-by-line discussions that were documented in the section worksheets, "Wrap-up Discussions" were held at the end of the HAZOP Study to en sure that these general topics were covered. The "Wrap-up Discussions" topics covered in the study included: u Safety / Fire Protection u Emergency Response u Procedures u Loss of Utilities u Siting / Control Room Location u Previous Incidents u Human Factors u Testing and Inspection u Maintenance u External Events u Other Hazards Analysis Studies Risk Matrix The HAZOP Study team members used a risk matrix to qualitatively assess the risk associated with each cause / consequence scenario that was developed during the study. The matrix used for this HAZOP Study is based on the information provided in the Contra Costa County Health Services Department (CCCHSD) RMPP Guidelines. Recommendations proposed by the HAZOP Study team are included in this report as Appendix A. Operating Procedure Current, clearly written standard operating procedures and safe work practices ensure that both experie nced and inexperienced employees, including contract employees, will respond in a safe, consistent and prescribed manner. The Pittsburg Water Treatment Plant developed a written operating procedures manual, satisfying the requirements of Section 2760.3 of the CalARP regulation, to ensure that written procedures/practices are developed, reviewed, implemented and annually certified as reflective of current plant practice. These procedures are available in the control room for each process, and include the following sections: Section I: Introduction Description of System System Modifications Treatment Emergency Power Storage and Distribution System Section II: Monitoring Monitoring Diagrams Flow Diagrams Settled Water Monitoring Backwash Recovery System Section III: Plant Operations Operator Certification Operational Procedure/Responsibilities Plant Start-Up Procedure Plant Shut-Down Procedure Filter Backwash Procedure Emergency Disinfection Equipment Descriptions Jar Testing Outline and Procedures Chemical Vendors List Section IV: Emergency Response Procedures Emergency Notification Plan Section V: Laboratory Procedures Training Every Plant employee is trained in the following: " The facilities Contingency Plan " Proper handling and storage techniques associated with the Hazardous Materials located on- site " Proper use and maintenance of both Emergency Response and Personal Protective Equipment, including MSA 401 breathing apparatus and chemical suits, and application of Chlorine Institute Emergency Kit B for ton containers. " The human and environmental health hazards associated with the hazardous materials on-site. This includes a review of Material Safety Data Sheets. " Emergency res ponse training and simple spill remediation " The location, operation and maintenance of fire extinguishers and spill control equipment " Facility shutdown procedures " The location of the facility's Contingency Plan Refresher training is given annually by the Plant Superintendent, or his designee, on an ongoing basis. New employees are trained immediately upon hiring. Employees who receive training so attest by signing and dating a training log. All training records are maintained at the Plant, with a copy sent to the Public Services Department Administrative Division. These records reflect weekly tailgate safety meetings presented and attended by all Plant personnel. The facility utilizes American Water Works Association (AWWA) safety training publications as a guide for its weekly safety discussions. Each year, the Plant uses AWWA's updated series of lecture topics on common utility safety practices. Mechanical Integrity A well-established mechanical integrity program e nsures that equipment critical to process safety is fabricated to meet process specifications, installed correctly, and maintained in a safe operating condition. It also allows maintenance employees to preemptively identify and correct equipment deficiencies to avoid associated incidents and down time. The Pittsburg Water Treatment Plant has therefore developed a mechanical integrity and maintenance program, satisfying the requirements of Section 2760.5 of the CalARP regulation, which is comprise of the programs and procedures show below. The program applies to pressure vessels and storage tanks, piping systems, relief and vent systems, emergency shutdown systems, controls and pumps and additional equipment deemed by the plant Superintendent to be important to safety. " The Superintendent, and when appropriate, consulting engineer, review(s) required mechanical details to ensure the equipment meets or exceeds all design specifications; is properly constructed; is suitable for i ts application; is designed in accordance with good engineering practice, and will meet the requirements for safety, reliability and product quality. " The Superintendent and maintenance staff conduct appropriate checks and inspections to ensure the equipment is installed properly and is consistent with the design specifications and manufacturer's instructions. " Maintenance employee training. The Plant reviews applicants for employment based on skills and experience pertinent to the job tasks. Additional skills training is provided on an as- needed basis. Maintenance employees are provided with an overview of the plant process, the hazards associated with the process, and safe work practices during initial employee training and annual refresher training. " Written maintenance procedures for process equipment. Specific maintenance activities are performed on a routine basis. Other maintenance activities are performed on an as-needed basis. All mainte nance activities at the Plant are logged in both the maintenance log and the plant (operations) log. Management of Change Changes within a stationary source are sometimes necessary to address safety, environmental and operational concerns. A change made in one part of the process or other processes may have unintended effects on other parts of the process because the stationary source is an integrated system. For this reason, any change in the systems for handling or storing chlorine or ammonia at the Plant would be scrutinized before they area made, to ensure the changes do not compromise the safety and integrity of the process and to avoid adverse effects to worker and public safety, and the environment. The Pittsburg Water Treatment Plant is a relatively small industrial facility. Since initial installation of the current chlorine and ammonia handling systems in 1990, no changes have been made to the chlorine or ammonia handling systems. However, if a change to these systems was planned, the following practice would be adhered to: Before any change is made to the chlorine or ammonia handling systems, the Water Plant Superintendent will ensure that all personnel complete training on the hazards associated with the change. This training will be completed prior to startup of the change. This would not apply to "replacement in kind" which is defined as replacements that satisfy the design specifications. Compliance Audits The Pittsburg Water Treatment Plant believes that ensuring the prevention program elements are functioning properly, that is, that they are complete, current, and applied in compliance with City policy, regulations and good process safety practices, is vital to the continuous improvement of the accidental release prevention program. Personnel perform internal compliance audits at least every three years, to review and evaluate the written documentation and records, and the implementation of the prevention program. Potential areas that can be improved within the prevention program elements are identified, and recommendations are formulated and implemented to ensure an effective and improved overall prevention program. The developed compliance audits program satisfies the regulatory requirement of Section 2760.8 of the CalARP regulation. An audit team will be assembled by the Plant Superintendent, and may include plant personnel, contract employees and/or consultants as appropriate. The team will utilize an audit protocol, to perform the following: " Assessment of the written prevention program elements " Review of records, including incident investigations, to assess implementation of the written prevention program elements " Employee interviews to assess fundamental level of understanding for applicable programs " Interviews with key personnel, who have primary responsibility for each prevention program element, to assess fundamental level of understanding. The audit team will formulate findings a nd recommendations for improvement. The results of the compliance audit will be communicated to all interested personnel, such as members of management, employees, during a closed meeting. The Superintendent will be responsible for reviewing the recommendations, determining appropriate resolution of each recommendation, and assigning responsibility for each recommendation. The facility will track and maintain records as to the final disposition of the recommendations formulated during compliance audits. Incident Investigation The Pittsburg Water Plant uses the "Facility Incident Check List" included in the facility Business Plan submitted annual to the CCCHSD. If an accidental release of chlorine or ammonia were to occur, the facility would use this checklist to document information specific to the accidental release. The investigation procedure following an incident involves four stages: gathering evidence, including interviewing witnesses and collecting evidence such as records or samples; analysis of the evidence, including identification of a root cause; developing conclusions and formulating recommendations. The result would be a written report on the incident, to be forwarded to Plant Management, the Public Services Safety Committee and CCCHSD and/or OSHA when appropriate. The investigation result, including the disposition of all formulated recommendations, would be reviewed with employees and contractors whose job tasks are relevant to the findings. However, this practice does not currently comply with CCCHSD RMPP guidelines (Section 6.5) or with the Occupation Safety and Health Administration (OSHA) Rule 1910.119, Process Safety Management of Highly Hazardous Chemicals, Section (m). During the HAZOP Study for the Plant, the study team recommended development of an incident investigation program that complies with the CCCHSD guidelines and OSHA Rule 1910.119. To date, this recommendation has not been acted upon. Employee Participation The Pi ttsburg Water Treatment Plant, like all divisions of the Public Services Department, relies on the expertise of employees (including seasonal and contract employees when appropriate) at all levels and disciplines to optimize operations and safety. This is achieved by consulting with employees to ensure consideration of their knowledge and experience in all applicable areas of the prevention program. This includes exchanging information with, and soliciting input and participation from Plant staff, contractors and others as appropriate. Hot Work Permit Controlling ignition sources is vital to the Pittsburg Water Treatment Plant's release prevention program. Therefore, it is critical that personnel at the Plant are notified when hot work (such as any spark-producing operation including use of power tools, grinding, burning, welding or brazing) is to be performed in a unit and that appropriate safety precautions are taken prior to the initiation of the work. While the Plant has not developed a formal, written, hot work permit program, the procedures to be followed are common knowledge to all Plant personnel, contractors and maintenance personnel occasionally provided to the plant by other divisions of the Public Service Department. That is, no work is to take place without the express consent of the Plant Superintendent. All work orders, purchases and contracts for work are required to have the Plant Superintendent's advance knowledge and signature prior to commencement of work. For a small industrial facility with few employees, this policy is effective, and enforceable. The Superintendent will perform an inspection of the area proposed for the hot work, prior to authorization of the work. He will ensure the following: " The source of ignition may be safely used, and only with approved apparatus. Personnel operating the equipment must be informed of the hazards and properly trained. " Combustible materials in areas that will be exposed during hot wo rk are protected or relocated. " Oil accumulations are removed. " Proper fire extinguishing equipment is available to personnel performing the hot work. " Personnel in the control room are notified prior to initiation of the hot work to make them aware of the ignition source. This allows personnel in the control room to quickly contact the fire district and personnel performing the hot work when continued use of the source of ignition becomes hazardous. Contractors The Plant relies on contractors to supplement the existing staff, in particular for facility construction, as well as equipment repair and maintenance. The Plant and all contractors are jointly responsible for safety, and must ensure that contractors are trained in and understand the following: " Work practices necessary to perform his or her job; " Hazards associated with a process; " Applicable sections of the emergency response procedure, including evacuation plans, and " Applicable safe w ork practices. It is also critical for contractors to inform Plant personnel of any unique hazards that they introduce while performing their work. Five Year Accident History The Pittsburg Water Treatment Plant compiled a five-year accident history for all accidental releases from covered processes that resulted in deaths, injuries, or significant property damage on site, or known offsite deaths, injuries, evacuations, sheltering in place, property damage or environmental damage. The compilation of this information satisfies the requirements of Section 2750.9 of the CalARP regulation. The five year accident history allows the Pittsburg Water Treatment Plant to explain to the community factors causing or contributing to accidental releases, the onsite and offsite impacts of accidental releases, and the procedural and technological changes made to minimize the likelihood that these accidental releases will not occur again. In a review of Water Plant operational and safety reports, there have been no documented accidental releases of ammonia or chlorine that have resulted in, or had the potential for, off-site impacts. Additionally, the Plant has not had releases of chlorine or ammonia in the last five years that resulted in injuries to facility or contract personnel due to exposure to these chemicals. Emergency Response Program Overall safety at the Pittsburg Water Treatment Plant is governed not only by the ability to prevent accidental releases of regulated substances, but to mitigate any accidental releases that may occur. The facility has developed and Emergency Response Plan, Emergency Response Procedures and Emergency Notification Plan, all of which are attached here as Appendix C. The Emergency Response Plan is used in the event of a fire or threatening Hazardous Materials release, and includes evacuation plans, notification to emergency responders, and the use of personal protective equipment in the event a spill response can be performed safely by on -site personnel. Emergency Response Procedures are written for a wide variety of emergencies, from power failures to disinfection equipment failure. All staff is trained in response and notification procedures. The Plant does not have its own fire brigade, and is therefore dependent on the Contra Costa Consolidated Fire District for response to fires in the area. All personnel will therefore evacuate the area and call "911" in the event of a fire. Properly trained employees may respond to incipient fires requiring one fire extinguisher after notifying the fire district. Annually, the fire district performs walk-throughs of the plant and its processes, and maintains a current copy of the Hazardous Materials Business Plan submitted to the CCCHSD. This pre-planning also ensures that members of the fire department are familiar with stationary source, the hazards of anhydrous ammonia and chlorine, resources available at the Plant, and the locations of those resources. Employees are tra ined on the emergency response program when initially hired, when the emergency response plan is revised, and when employees' responsibilities are changed. All employees receive annual refresher training on the emergency response program. Planned Changes to Improve Safety To date, there are no planned changes to improve safety at the Pittsburg Water Treatment Plant. However, the Superintendent and Public Services Department managers will meet to discuss refinements of the following procedures or processes: " Hot work permits formalization of policy, and proposal to include other personnel in review process when appropriate. " Mechanical Integrity formalization of the procedures for reviewing equipment, and proposal to include additional personnel in review process. " Incident investigation procedures to comply more fully with current OSHA, CalARP and CCCHSD regulations. |